This invention relates to an hydraulic puller system, and more particularly to an hydraulically powered locking puller device having a base assembly about a central axis, a camming assembly circumferentially about the base assembly, and a readily removable hydraulic module axially-centered in the base assembly. The invention also relates to a method for convenient assembly, and also disassembly, of parts of the puller device, especially as modular units.
This teaching provides the benefits of a locking puller in combination with the benefits of an hydraulically powered system without sacrificing economy of structure and with the advantage of ease of removal and reattachment of the part most subject to wear failure, namely the hydraulic system.
Locking puller devices have heretofore been known, as illustrated in Knight U.S. Pat. No. 2,303,560, and also in the United States patents of Brandt and Somerville, namely U.S. Pat. No. 4,007,535, issued Feb. 15, 1977, and U.S. Pat. No. 4,068,365 issued Jan. 17, 1978. Brandt and Sommerville U.S. Pat. No. 4,007,535 suggests manufacturing an hydraulic cylinder in the center bore in place of a threaded rod. Manufacturing hydraulic components within a center bore is difficult and expensive. An hydraulic puller device, and one specifically having an externally threaded hydraulic cylinder for a jaw assembly, is illustrated in Hill U.S. Pat. No. 1,581,057, issued Apr. 13, 1926. Still other hydraulic pullers have been placed on the market, but lack convenient locking or camming of puller elements and generally require awkward claw or jaw assemblies and awkward arrangements for the components.
Insofar as is known, all prior art hydraulic puller teachings have totally failed to address and have not suggested the formation of an hydraulically powered locking puller permitting easy discrete separation of the entire hydraulic system from remaining parts of the locking puller without need to dismantle the hydraulic system and without need to dismantle or loosen or adjust any other part or assembly of parts of the locking puller.
The need for reliable easy-to-use hydraulic pullers is primarily for pulling large gears or bearings or other elements frozen or friction fitted on relatively large shafts or structures of large equipment. Tackling such a job generally requires a relatively large puller and one not easily shifted in position by human muscle strength. Hoist equipment for movement of the puller into position is frequently needed.
Insofar as known, no one has devised an hydraulically powered locking puller satisfactory for such jobs and equipped with elements to which a chain or other connector for hoist movement of the puller is conveniently affixed.